ACER's EU-wide cost-of-new-entry dataset has been open since July
Serguey Asael Shinder2 min readACER published the first open-access EU-wide dataset of cost of new entry values - the EU CONE Dataset - on 30 July 2026, together with an interactive dashboard. It carries economic parameters for new electricity resources: estimated capital and operational costs across generation technologies, and for demand-side flexibility. The stated purpose is long-term system modelling.
ACER is direct about the problem it replaces. Until now only fragmented data existed at EU level, which made cross-country comparison difficult and, in the agency's own words, increased the risk that adequacy assessments and investment signals would rely on inconsistent cost assumptions.
We are flagging it in late September rather than in July for a mundane reason worth stating: ACER's news feed carries no publication dates, so items surface whenever a reader's tooling notices them. The dataset has been available for roughly two months.
What it means
The significance is not the numbers but the fact that everyone now has to use the same ones, or explain why not. A CONE value is an input to capacity adequacy assessment - it is the benchmark against which a market is judged capable or incapable of attracting new capacity, and therefore whether intervention is justified. When each member state brings its own cost assumptions, two adequacy studies can disagree without either being wrong, because they disagree about what a new gas turbine or a battery costs. Harmonising the input does not harmonise the conclusion, but it moves the argument from "whose numbers" to "whose method", which is the argument that can actually be settled.
The demand-side flexibility parameters are the part to watch. Generation costs are well-travelled ground with decades of published comparables; flexibility is where estimates vary most and where a common reference has the largest effect on outcomes, because an adequacy assessment that prices flexibility cheaply concludes that less firm capacity is needed. Anyone modelling a national system against EU benchmarks should read ACER's flexibility assumptions before their own, since divergence there will drive more of the difference than the technology capex lines will.
Practical note: the dashboard exists precisely because a dataset nobody opens has no effect on practice. If the CONE figures are going to discipline national assumptions, it will be because reviewers can pull up the EU reference in one click during a consultation - not because the file was published.